Audio programs, for e.g. Voice over IP, audio streaming, etc., are well-known, and software for these programs are readily available for installation on a computer. The data stream may be provided to an external device, such as headphones, mixers, loudspeakers, headsets, etc. Typically, a wired connection has been made via audio jacks for providing audio to speakers and receiving input from microphones.
However, the wired connections tying a user to the computer are in many situations not advantageous, and consequently, wireless devices may be preferred. Wireless devices may be connected directly to the computer, using e.g. the Bluetooth standard. It may however for some applications be advantageously to connect the computer to a wireless RF hub using a USB interface.
The communication of audio data between the USB interface and the RF hub may prove challenging, especially for low latency applications, such as telephony.
It has been suggested to use an adaptive mode in which the computer controls the audio transfer rate and the USB has to update a master clock e.g. every one millisecond. However, this requires a complex frequency synthesizer, and may not be an available option for all computer operating systems in that different operating systems provide different control signals.
It is also known to use a synchronous data stream and provide a buffer to buffer incoming data having a first sample rate and outputting data at a second sample rate. However, for low latency data, such as in telephony systems, the delay caused by the buffer is typically not acceptable.
In another approach, the digital signal provided by the USB interface is converted into an analog signal, and the analog signal is provided to an ND converter providing the converted digital signal to the RF wireless device. However, this method is complex, requires a D/A and an ND converter, and results in the loss of data and thus a loss of signal information at each conversion.
Thus, there is a need for an improved communication of audio data between a USB interface and a wireless RF hub.